Various configurations have been developed for milking parlors. In a typical modern milking parlor, several cows are milked simultaneously utilizing various types of automated equipment, particularly automated milking claw detachers. Among the configurations for milking parlors is the so called herringbone arrangement in which several cows are led into the milking parlor at the same time and are lined up at a diagonal to the length of the milking parlor, with the rear of the cow facing the milking parlor pit where an attendant can reach the udder of each cow and attach the teat cups.
To cause the cows to be properly aligned in the herringbone parlor configuration, the cows are generally led into the parlor in single file adjacent to the milking machines, with the first cow being urged into the proper diagonal position by an exit gate which, in its closed position, extends at a diagonal to the lengthwise direction of the milking parlor. To constrain the cows as they enter the milking stalls and to cause the cows following the first cow to assume the diagonal position, a restraining structure such as a fence or bar is mounted along the length of the milking stations in the parlor at a distance away from the milking stations which is less than the front leg to back leg length of a cow. When the first cow reaches the exit gate and assumes a diagonal position to the milking stall, the other cows will be forced to do the same, thus causing all to properly line up in the herringbone milking parlor.
In a typical herringbone parlor design, after all the cows have finished milking, the exit gate at the end of the parlor is opened and the cows leave the parlor in single file. However, it has been found that this somewhat slows down the exit of the cows and can result in pushing and shoving between the cows which may further slow down the exit procedure. In addition, the restraining fence or barrier which is parallel to the milking machines is typically formed of metal pipe and occasionally the cows will attempt to the climb over the pipe and get entangled in it.
In some herringbone milking parlor designs, individual exit gates have been built to form the restraining barrier so that each cow can be individually released from the milking stall when it has finished milking. However, such individual exit gates are more expensive and necessarily require more complicated control and operating structures. Another approach to exiting has been to provide an exit barrier parallel to the milking machines which is held in the normal lower position adjacent to the front or "brisket" of the cow during milking but is raised to allow all of the cows to exit at once when all cows have finished milking. By raising the entire barrier in this manner, all the cows can very quickly leave the milking parlor with a minimum of pushing and shoving.